Apparatus for insuring automatic closure of an engine throttle valve upon release of the accelerator pedal

ABSTRACT

An apparatus is provided for insuring closure of a throttle valve in a suction passage in an internal combustion engine when an acceleration member such as an acceleration pedal or the like is released. The throttle valve is urged by a spring to its closed position and a normally closed clutch is incorporated in an operation mechanism which couples the throttle valve and the acceleration pedal. The clutch is opened by an electro magnet when both a first detecting switch is closed upon release of the acceleration pedal and a second detecting switch is closed when the throttle valve remains in its open position.

United States Patent n 1 Maeda [54] APPARATUS FOR INSURING AUTOMATIC CLOSURE OF AN ENGINE THROTTLE VALVE UPON RELEASE OF THE ACCELERATOR PEDAL [75] Inventor: Noriyuki Maeda, Sengoku, Tokyo,

Japan [73] Assignee: Honda Giken Kogyo Kabushiki Kaisha, Tokyo, Japan [22] Filed: Dec. 15, 1970 [21] Appl. No.: 98,379

[30] Foreign Application Priority Data UNITED STATES PATENTS MacMillan...-. ..l23/l98 DB 1 Mar. 27, 1973 Primary Examiner-Charles J. Myhre Assistant Examiner-Randall Heald Att0rney--Waters, Roditi, Schwartz & Nissen [57] ABSTRACT An apparatus is provided for insuring closure of a throttle valve in a suction passage in an internal combustion engine when an acceleration member such as an acceleration pedal or the like is released. The throttle valve is urged by a spring to its closed position and a normally closed clutch is incorporated in an operation mechanism which couples the throttle valve and the acceleration pedal. The clutch is opened by an electro magnet when both a first detecting switch is closed upon release of the acceleration pedal and a second detecting switch is closed when the throttle valve remains in its open position.

9 Claims, 2 Drawing Figures PATENTEDHARZYISIS 722 491 i df I w: 1

LVVJ J 8 /5 INVENTOR APPARATUS FOR INSURING AUTOMATIC CLOSURE OF AN ENGINE THROTTLE VALVE UPON RELEASE OF THE ACCELERATOR PEDAL BRIEF SUMMARY OF THE INVENTION This invention relates to apparatus for automatically closing a throttle valve in a suction passage in an internal combustion engine for a motorcar or the like.

If, during the operation of an internal combustion engine, the throttle valve remains open due to a defect in an operation mechanism for opening and closing the valve, the engine continues to operate at a high speed,

which is dangerous.

An object of this invention is to provide an apparatus removing the danger as indicated above and it is characterized in that the throttle valve is urged by a return spring to its closed position side and a normally closed clutch is incorporated in an operation mechanism which actuates the throttle valve from an acceleration operation member, the clutch being automatically opened when the throttle valve is not closed when the operation member is released from its operative condition.

The clutch may be an electromagnetic clutch which is opened when a solenoid is energized. In this case, there are provided a first switch which is closed when the acceleration operation member is released from its operative condition and a second detecting switch which is closed when the throttle valve is in its open position, the two switches being interposed in an electric circuit connecting the solenoid and an electric source.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a diagrammatic illustration of an embodiment of this invention and FIG. 2 is an enlarged sectional view of a portion thereof.

DETAILED DESCRIPTION Referring to the drawing, numeral 1 denotes an internal combustion engine, numeral 2 denotes a suction opening thereof, and numeral 3 denotes a suction passage connected to the suction opening 2. A throttle valve 4 is mounted within the passage 3 rigidly on a shaft 5 so as to be freely tumable to open and close the passage. The valve 4 is urged to its closing position by a bias means constituted by a return spring 6, and a normally closed clutch 9 is incorporated in an operation mechanism 8 which actuates the valve 4 by an acceleration operation member 7 such as an acceleration pedal or the like. This will be explained in greater detail with reference to the illustrated embodiment. Namely, the clutch 9 comprises a pair of clutch plates 9a and 9b, clutch plate 9a being secured to the shaft 5 and being acted on by the return spring 6 interposed between the clutch plate 9a and the outer wall surrounding the suction passage 3. The clutch plate 9b is secured to one end of a slidable shaft 12 arranged to retract against the action of a spring 11 when an electromagnetic solenoid is activated. The clutch plate 9b and-the operation member 7 are interconnected through a flexible wire 13 and a bell crank 14 so that the operation mechanism 8 is controlled by the member 7. Numeral 15 denotes a thrust bearing interposed between the spring 11 and the clutch plate 9b.

There are provided a first detecting switch 16 which is coupled to member 7 and is closed when the member 7 is released from operation, and a second detecting switch 17 which is closed by detecting that the throttle valve 4 is in its open position. The two switches 16 and 17 are connected in series in an electric circuit containing the electromagnetic solenoid 10 and an electric source 18. The first detecting switch 16 comprises a pressure switch element coupled for movement with a pressure receiving plate 19 provided at the front surface of the operation member 7, and the second detecting switch 17 is so arranged that it is actuated by a side arm 20 on the throttle valve 4 for being opened and closed thereby.

The operation of the illustrated embodiment is as follows:

The clutch 9 is normally closed. Therefore, in this condition, if the acceleration pedal 7 is depressed, the throttle valve 4 is forced to open against the action of the return spring 6 through the operation mechanism 8. If, then, the acceleration pedal 9 is released from its depressed or operated condition, the throttle valve 4 is allowed to return to its closing position by the action of the return spring 6. When, however, due to a deficiency in the operation mechanism 8 such as, for example, rust which freezes the actuating wire 13 or thelike, the throttle valve 4 is not returned to its closing position when the acceleration pedal 7 is released, this condition is detected by closing of the switches 16 and 17, so that the electromagnetic solenoid 10 I is energized thereby and the shaft 12 is retracted against the action of the spring 11, whereby the clutch 9 is opened. Accordingly, the throttle valve 4 is separated from the operation mechanism 8 and is allowed to be automatically closed by the action of its own return spring 6. Thus, the danger of the throttle valve 4 remaining open is prevented.

Thus, according to this invention, when the throttle valve is not returned to its closed position due to a deficiency in the operation mechanism, when the acceleration operation member has been released from its operation condition, the clutch is opened to separate the throttle valve from the operation mechanism so that the valve is closed automatically by its own return spring, and accordingly the danger that the throttle valve remains open is simply and positively prevented.

What is claimed is:

1. In combination: a throttle valve in a suction passage of an internal combustion engine, an acceleration operation member operatively engageable to open the throttle valve, means for automatically insuring closure of the throttle valve when the acceleration operation member is released, the latter said means comprising bias means acting on said throttle valve to urge the same to its closed position, operation means coupling said throttle valve and said acceleration operation member such that the throttle valve follows the opera- 7 tion of said acceleration operation member against the action of said bias means, and detection means for detecting the position of said acceleration operation member and the position of said throttle valve to decouple the operation means for the throttle valve and permit the throttle valve to return to its closed position under the action of said bias means when the operation member has been released and the throttle valve remains open.

2. The combination as claimed in claim 1 wherein said operation means comprises a clutch which is normally closed to enable the throttle valve to follow the operation of the acceleration operation member, said detection means including means for opening the clutch when the operation member has been released and the throttle valve remains open.

3. The combination as claimed in claim 2 wherein said means for opening the clutch comprises an electromagnet coupled to said clutch.

4. The combination as claimed in claim 3 wherein said detection means comprises a first switch coupled to said acceleration operation member to close when the acceleration operation member is released, a second switch coupled to said throttle valve to close when the throttle valve is opened,-and means connecting the first and second switches in a circuit with the electromagnet so that the electromagnet is energized when the first and second switches are closed.

5. The combination as claimed in claim 4 wherein said first and second switches are connected in series.

6. The combination as claimed in claim 4 wherein said clutch comprises first and second opposed clutch members coupled respectively to said throttle valve and said electromagnet, said bias means comprising a spring acting on said first clutch member.

7. The combination as claimed in claim 6 wherein said operation means comprises an actuating member operatively engaging said second clutch member, and coupled to said acceleration operation member.

8. The combination as claimed in claim 7 comprising a second spring acting on the second clutch member to urge the second clutch member into engagement with the first clutch member.

9. The combination as claimed in claim 7 wherein said actuating member is a flexible wire. 

1. In combination: a throttle valve in a suction passage of an internal combustion engine, an acceleration operation member operatively engageable to open the throttle valve, means for automatically insuring closure of the throttle valve when the acceleration operation member is released, the latter said means comprising bias means acting on said throttle valve to urge the same to its closed position, operation means coupling said throttle valve and said acceleration operation member such that the throttle valve follows the operation of said acceleration operation member against the action of said bias means, and detection means for detecting the position of said acceleration operation member and the position of said throttle valve to decouple the operation means for the throttle valve and permit the throttle valve to return to its closed position under the action of said bias means when the operation member has been released and the throttle valve remains open.
 2. The combination as claimed in claim 1 wherein said operation means comprises a clutch which is normally closed to enable the throttle valve to follow the operation of tHe acceleration operation member, said detection means including means for opening the clutch when the operation member has been released and the throttle valve remains open.
 3. The combination as claimed in claim 2 wherein said means for opening the clutch comprises an electromagnet coupled to said clutch.
 4. The combination as claimed in claim 3 wherein said detection means comprises a first switch coupled to said acceleration operation member to close when the acceleration operation member is released, a second switch coupled to said throttle valve to close when the throttle valve is opened, and means connecting the first and second switches in a circuit with the electromagnet so that the electromagnet is energized when the first and second switches are closed.
 5. The combination as claimed in claim 4 wherein said first and second switches are connected in series.
 6. The combination as claimed in claim 4 wherein said clutch comprises first and second opposed clutch members coupled respectively to said throttle valve and said electromagnet, said bias means comprising a spring acting on said first clutch member.
 7. The combination as claimed in claim 6 wherein said operation means comprises an actuating member operatively engaging said second clutch member, and coupled to said acceleration operation member.
 8. The combination as claimed in claim 7 comprising a second spring acting on the second clutch member to urge the second clutch member into engagement with the first clutch member.
 9. The combination as claimed in claim 7 wherein said actuating member is a flexible wire. 